Influence of inspiratory assistance on ventilatory control during moderate exercise.
Influence of inspiratory assistance on ventilatory control during moderate exercise.
复制标题
适度运动时吸气辅助对通气控制的影响。
DOI：
10.1152/jappl.1987.62.2.551
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Whipp,BJ
中科院分区：
文献类型：
--
作者：
Poon,CS;Ward,SA;Whipp,BJ
在5名健康受试者中，我们利用改良的正压呼吸机(IEEE Trans)，研究了适度运动时呼吸系统受控机械负荷对呼吸机控制的影响。生物医学。英语。BME-33：361-365,1986)。我们特别感兴趣的是，当呼吸机替代了对恒定负荷循环的正常呼吸反应的一部分时，是否维持了等睡眠。机械卸载是通过与瞬时流量成恒定比例在整个吸气过程中“辅助”气流来实现的。施加两个中等程度的援助(A1=1.5和A2=3.0cmH2O×L-1×S)。辅助治疗使每分钟通气量(VE)即刻增加(吸气时间缩短，潮气量增加)，呼气末二氧化碳分压(PETCO2)下降。约10-15分钟后，S，吸气阻断压(P100)下降，并在新的稳态VE和PETCO2几乎恢复到他们的对照运动水平。适度的残余过度换气[增量PETCO2=-0.9Torr(A1)和-1.6Torr(A2)]，在统计学上并不显著，与VE预计的更大的增加形成了明显的对比，如果没有代偿性的机械驱动减少(P100的下降就是证据)。与使用阻性负载的早期研究一致(J.Appl.物理。1973年35：361-366和生理学报。斯坎德。120：557-565,1984)，这些观察结果表明，适度运动时的呼吸机能受到控制，以补偿呼吸机械负荷的轻微变化，从而使VE保持在与代谢率相适应或接近的水平。
In five healthy subjects, we studied the effects of controlled mechanical unloading of the respiratory system on ventilatory control during moderate exercise, utilizing a modified positive-pressure ventilator (IEEE Trans. Biomed. Eng. BME-33: 361–365, 1986). We were especially interested in whether isocapnia was maintained when a portion of the normal ventilatory response to constant-load cycling was subserved by the ventilator. The mechanical unloading was achieved by “assisting” airflow throughout inspiration in a constant proportion to instantaneous flow. Two modest degrees of assistance (A1 = 1.5 and A2 = 3.0 cmH2O X l-1 X s) were imposed. The assistance caused minute ventilation (VE) to increase immediately (inspiratory time shortening and tidal volume rising) and end-tidal PCO2 (PETCO2) to fall. Some 10–15 s later, inspiratory occlusion pressure (P100) decreased, and in the new steady-state VE and PETCO2 were virtually restored to their control exercise levels. The modest residual hyperventilation [delta PETCO2 = -0.9 Torr (A1) and -1.6 Torr (A2)], which was not significant statistically, contrasted markedly with the much larger increase predicted for VE had there been no compensatory reduction in ventilatory drive (as evidenced by the fall in P100). Consistent with earlier studies utilizing resistive loading (J. Appl. Physiol. 35: 361–366, 1973 and Acta Physiol. Scand. 120: 557–565, 1984), these observations suggest that ventilatory drive during moderate exercise is controlled to compensate for modest changes in respiratory-mechanical load, so that VE is preserved at a level appropriate to metabolic rate or nearly so.